Bipolar battery and plate

ABSTRACT

A bipolar battery plate for a bipolar battery is disclosed. The bipolar battery plate has a frame, a substrate positioned within the frame, a first lead layer positioned on one side of the substrate, a second lead layer positioned on another side of the substrate, a positive active material (PAM) positioned on a surface of the first lead layer, and a negative active material (NAM) positioned on a surface of the second lead layer. The substrate has a plurality of perforations, and a plurality of standoffs integrally formed on opposing side surfaces thereof. The first and second lead layers are electrically connected to each other through the plurality of perforations.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation-in-part of application Ser.No. 13/229,251 with priority to Sep. 9, 2011, entitled “Bipolar Batteryand Plate,” which is currently pending and incorporated herein byreference.

FIELD OF THE INVENTION

The invention relates to a battery and in particular to a bipolarbattery having a series of bipolar battery plates.

BACKGROUND

A conventional bipolar battery generally includes electrodes having ametallic conductive substrate on which positive active material formsone surface and negative active material forms the opposite surface. Theactive materials are retained by various means on the metal conductivesubstrate which is nonconductive to electrolyte ions. The electrodes arearranged in parallel stacked relation to provide a multi-cell batterywith electrolyte and separator plates that provide an interface betweenadjacent electrodes. Conventional mono-polar electrodes, used at theends of the stack are electrically connected with the output terminals.Most bipolar batteries developed to date have used metallic substrates.Specifically, bipolar lead-acid systems have utilized lead and alloys oflead for this purpose. The use of lead alloys, such as antimony, givesstrength to the substrate but causes increased corrosion and gassing.

In most known plates for bipolar batteries, the positive activematerial, usually in the form of a paste is applied to the metallicconductive substrate on one side while the negative active material issimilarly applied to the opposite side. The plates may be contained by aframe which seals the electrolyte between plates so that it cannotmigrate through the plate.

In U.S. Pat. No. 4,275,130, a bipolar battery construction 20 isdisclosed having a plurality of conductive biplates 21. Each bipolarplate 21 may include a composite, substrate sheet 34 including acontinuous phase resin material, which is nonconductive to electrolyteions. The composite substrate sheet 34 also includes uniformlydistributed, randomly dispersed conductive fibers 33 embedded in thematerial. The binder resin is a synthetic organic resin and may bethermosetting or thermoplastic. The composite substrate sheet 34 hassubstantially flat opposite side faces 35 which include at theirsurfaces exposure of portions of the embedded graphite fibers 33. Theembedded graphite fibers not only provide electrical conductivitythrough the substrate sheet 34, but also impart to the thermoplasticmaterial a high degree of stiffness, rigidity, strength and stability.Substrate sheet 34 may be made in any suitable manner such as bythoroughly intermixing the thermoplastic material in particle form withthe graphite fibers. The mixture is heated in a mold and then pressureformed into a substrate sheet of selected size and thickness. After thesheet has been cured, the substantially flat side faces 35 may bereadily treated or processed, as for example by buffing, to eliminatepinholes or other irregularities in the side faces.

As disclosed, lead stripes are bonded to the composite substrate sheet34 by known plating processes. On the positive side face 35, the facialareas between lead stripes 38 are covered by a coating of corrosionresistant resin 36 suitably a fluorocarbon resin such as Teflon(polytetrofluoroethylene) which protects against anodic corrosion of theadjacent graphite fibers and polyethylene of the substrate 34. On thenegative side face 35, facial areas between lead stripes 37 may beprotected by a thin coating of resin impermeable to electrolyte such asa polyethylene coating 36 a. In fabrication of the bipolar plate 21 andafter the composite substrate sheet 34 has been formed, a thin Teflonsheet may be bonded to the positive side surface 35. Prior to bonding,window like openings corresponding in length and width to the leadstripes are cut. Plating thereafter will bond the lead in stripes 38 tothe exposed conductive graphite surfaces on the substrate side face 35.The same fabrication process may be utilized on the negative side face35 to coat the nonstriped areas with polyethylene or other likematerial. Plating of the negative stripes may be achieved as with thepositive stripes.

A separator plate 23 serves to support the positive active material 24and the negative active material 25 and may be made of a suitablesynthetic organic resin, preferably a thermoplastic material such asmicroporous polyethylene.

Battery construction 20 includes a plurality of conductive bipolarplates 21, peripheral borders or margins thereof being supported andcarried in peripheral insulating casing members 22. Interleaved andarranged between bipolar plates 21 are a plurality of separator plates23 The separator plates carry positive active material 24 on one sidethereof and negative active material 25 on the opposite side thereof.The casing members 22, together with the bipolar plates 21 and separatorplates 23, provide chambers 26 for containing electrolyte liquid. Ateach end of battery construction 20, standard bipolar plates 21interface with current collecting plates, where 27 is the negativecollector plate and 28 is the positive collector plate. Externally ofend collectors 27 and 28 are provided pressure members 30 interconnectedby rods 31 having threaded portions for drawing the pressure membersplates together and applying axial compression to the stackedarrangement of bipolar plates and separator plates.

The bipolar plate 21 is lightweight, rigid, but includes joint linesbetween the lead stripe edges and protective coatings to resistcorrosion and structural deterioration of the substrate. Furthermore, aplating process is required in order to bond the lead stripes 37, 38 tothe conductive substrate having graphite fibers. Conductivity is limitedby the size and amount type of graphite fibers in the substrate.Additionally, a plurality of bipolar plates 21 and layers are requiredto sit in separate casing members 22 and an external frame, all of whichrequire further processing steps for more parts. The bipolar batteryconstruction 20 is a complicated design having many layers of materialsand substrates assembled in multiple chambers 26 and bodies 43 that aresecured together by a complex external frame.

SUMMARY

It is an object of the present invention, among other objects, toprovide a bipolar battery having a simplified bipolar plate design,wherein the active materials are encased within an insulated framehaving a moldable substrate with perforations to improve conductivitybetween the active materials. Furthermore, the bipolar battery isinexpensive to produce and does not require a complex external frame tosupport the bipolar plates.

Each bipolar battery plate has a frame, a substrate positioned withinthe frame, a first lead layer positioned on one side of the substrate, asecond lead layer positioned on another side of the substrate, apositive active material (PAM) positioned on a surface of the first leadlayer, and a negative active material (NAM) positioned on a surface ofthe second lead layer. The substrate has a plurality of perforations anda plurality of standoffs integrally formed on opposing side surfacesthereof. The first and second lead layers are electrically connected toeach other through the plurality of perforations.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is explained in more detail below with reference to theFigures shown in the drawings, which illustrate exemplary embodiments ofthe present invention wherein:

FIG. 1 is a front view of a bipolar plate according to the invention;

FIG. 2 is a sectional view of the bipolar plate taken along the line 2-2of FIG. 1;

FIG. 3 is a perspective view of a bipolar battery according to theinvention;

FIG. 4 is an exploded perspective view of the bipolar battery of FIG. 4;

FIG. 5 is a partial sectional view of the bipolar battery according tothe invention having a casing;

FIG. 6 is another partial sectional view of the bipolar batteryaccording to the invention without the casing;

FIG. 7 is a close up view of the bipolar plate according to theinvention showing a perforation in a substrate of the bipolar plate; and

FIG. 8 is another close up view of the bipolar plate according to theinvention, showing a non-conductive frame of the bipolar plate; and

FIG. 9 is another close up view of the bipolar plate according to theinvention, showing another non-conductive frame of the bipolar plate.

FIG. 10 is a perspective view of the bipolar plate according to anadditional embodiment of the invention.

DETAILED DESCRIPTION OF THE EMBODIMENT(S)

The invention is explained in greater detail below with reference to thedrawings, wherein like reference numerals refer to the like elements.The invention may, however, be embodied in many different forms andshould not be construed as being limited to the embodiments set forthherein; rather, these embodiments are provided so that the descriptionwill be thorough and complete, and will fully convey the concept of theinvention to those skilled in the art.

With respect to FIGS. 1-10, a bipolar battery 100 according to theinvention includes a plurality of bipolar plates 10, spacers 22 holdingan electrolyte 20, and terminal end sections 30. Each of thesecomponents are stacked together to complete a bipolar battery 100according to the invention, which is an adaptable design with minimalnumber of parts devoid a complex exterior support structure.

Now with reference to FIGS. 1 and 2, a bipolar plate 10 according to theinvention is discussed. The bipolar plate 10 includes a frame 11, asubstrate 12, a plurality of perforations 13 along and extending througha front and rear surface of the substrate 12, lead foils 14, a firstactive material 16, and a second active material 18.

In general, the substrate 12, lead foils 14, first active material, 16and second active material are encased within the frame 11, whichprovides support and protection for the bipolar plate 10. The substrate12 is positioned in a center of the frame 11, the lead foils 14 arepositioned on both sides of the substrate, and the active materials 16,18 are then positioned over the lead foils 14. The frame 11 isnon-conductive. In the embodiment shown, the frame 11 is a moldableinsulative polymer, such as polypropylene, acrylonitrile butadienestyrene (ABS), polycarbonate, copolymers, or polymer blends. Because theframe 11 is moldable, the number of shape and size configurations areabundant, which provides a bipolar plate 10 according to the inventionthat can be tailored to different uses.

In the embodiment shown, the frame 11 has a generally rectangular shape,which provides support for a substrate 12 when positioned in the frame11. The frame 11 is a casing for the bipolar plate 10, as well as thebipolar battery 100. The outer surface of the frame 11 is the outersurface of the bipolar plate 10 and bipolar battery 100. The surface ofthe frame 11 is generally flat, and in particular, along the exteriorsurfaces of the frame 11. The frame 11 supports itself, as well as thebipolar plate 10 when assembled with the spacers 22 and terminalssections 30, especially when the bipolar plate 10 sits upright against aflat opposing surface.

The frame 11 further includes substrate receiving passageways 11 a andmaterial receiving passageways 11 b, as shown in FIG. 2. The substratereceiving passageways 11 a are grooves or channels, while the materialreceiving passageways 11 b are openings in the frame 11 that receive thelead foils 14 and active materials 16, 18 on both stackable side of thebipolar plate 10.

The substrate receiving passageways 11 a is a groove used to receive andsecure the substrate 12, when the substrate 12 is positioned within theframe 11. Other configurations of substrate receiving passageways 11 aare possible, including notches, indentations, recesses or any securingmechanism that secures the substrate 12 within the frame 11. Forinstance, the substrate 12 could be secured to the frame 11 using a weldor by adhesive, or by a fastener. However, in the embodiment shown, thesubstrate 12 is secured in the substrate receiving passageways 11 aduring manufacturing the bipolar plate 10.

Each material receiving passageway 11 b is positioned in a substantialcenter of the frame 11 split from each other by the substrate 12, whenthe substrate 12 is positioned within the substrate receivingpassageways 11 a. Furthermore, the lead foils 14 and active materials16, 18 are encased within an outer surface plane of the frame 11. Thesepair of cavities are dimensioned to securely receive the lead foils 14and active materials 16, 18 within the frame 11.

In the embodiment shown, the substrate 12 is a separate piece ofinsulative material with respect to the frame 11, with the substrate 12is received and secured within the substrate receiving passageways 11 aof the frame 11. However, the frame 11 and substrate 12 can be formedtogether, as a monolithic structure, generally from the same material.During manufacturing, the frame 11 and the substrate 12 are constructedas one piece from the same material. This can be performed through aprocess such as injection molding, or other known methods.

The substrate 12 in the embodiment shown is an insulative plastic thatis generally non-conductive, namely, polypropylene, acrylonitrilebutadiene styrene (ABS), polycarbonate, copolymers, or polymer blends inthe embodiment shown. As briefly discussed above, the substrate 12 maybe prepared from the same material as the frame 11, regardless if theframe 11 and substrate 12 are prepare from a one piece construction.

In an alternative embodiment, as shown in FIG. 7, the substrate 112 isgenerally nonconductive, being prepared from insulative plastic.However, conductive fibers and material are homogeneously dispersedthroughout the insulative plastic. For instance, the substrate 112 maybe prepared from a non-corrosive plastic sold by Integral Technologies,Inc, under the trade name Electriplast, which includes highlyelectrically conductive areas. The substrate 112, as shown in FIG. 7,includes a non-conductive resin-based material or thermoplastic 112 awith a micron powder(s) of conductor particles and/or in combination ofmicron fiber(s) 112 b substantially homogenized within the resin orthermoplastic 112 a. As clearly shown in FIG. 7, the conductor particlesor fibers 112 b are homogenized throughout the body of the resin orthermoplastic 112 a. In this example, the diameter D of the conductorparticles of the conductor particles or fibers 112 b in the powder isbetween about 3 and 12 microns. The conductor fibers of the conductorparticles or fibers 112 b have a diameter of between about 3 and 12microns, typically in the range of 10 microns or between about 8 and 12microns, and a length of between about 2 and 14 millimeters. The micronconductive fibers of the conductor particles or fibers 112 b may bemetal fiber or metal plated fiber. Further, the metal plated fiber maybe formed by plating metal onto a metal fiber or by plating metal onto anon-metal fiber. Exemplary metal fibers include, but are not limited to,stainless steel fiber, copper fiber, nickel fiber, silver fiber,aluminum fiber, or the like, or combinations thereof. Exemplary metalplating materials include, but are not limited to, copper, nickel,cobalt, silver, gold, palladium, platinum, ruthenium, and rhodium, andalloys of thereof. Any platable fiber may be used as the core for anon-metal fiber. Exemplary non-metal fibers include, but are not limitedto, carbon, graphite, polyester, basalt, man-made andnaturally-occurring materials, and the like. In addition, superconductormetals, such as titanium, nickel, niobium, and zirconium, and alloys oftitanium, nickel, niobium, and zirconium may also be used as micronconductive fibers and/or as metal plating onto fibers.

The conductor particles and/or fibers 112 b are substantiallyhomogenized within the resin or thermoplastic 112 a. The substrate 112includes controlled areas of conductive surfaces on the substrate 112,wherein the conductive materials from the conductive particles or fibers112 b are exposed through the resin or thermoplastic 112 a, which areconductively connected by the homogenization process. The conductivesurfaces of the substrate 112 are controlled by further manufacturingtechniques, such as etching or abrasive blasting, wherein the surface isroughened by chemical or by propelling a stream of abrasive materialagainst the surface under high pressure. The conductor particles and/orfibers 112 b are then exposed, and conductive areas of the substrate 112are provided. The process provides a substrate 112 having a controlledamount of conductivity, including the size and area of conductivity.

It is also possible that the substrate 112 includes a combination ofboth conductive particles, powders, and/or fibers 112 b, that aresubstantially homogenized together within an insulative resin orthermoplastic 112 a during a molding process. The homogenized materialis molded into a polygonal shape, as a substrate 112, which accommodatesvarious custom designs or properties required for the bipolar plate 10according to the invention. The substrate 112 may then be molded withthe frame 11 in a single manufacturing technique. This allows thebipolar plate 10 and bipolar battery 100 to be simplified, whereinminimal parts are used and production steps are eliminated. Furthermore,the properties of the substrate 112 and battery 100 may be focused byproviding and controlling conductive areas along the surface of thesubstrate 112. Since the frame 11 is insulative and the substrate 12,112 is positioned in the substrate receiving passageways 11 a, thebipolar plate 10 can act as a frame of the bipolar battery 100 whenassembled.

During manufacturing, the substrate 12 is either insert molded into thesubstrate receiving passageways 11 a, or the frame 11 is over moldedover the substrate 12. However, if the frame 11 and the substrate 12 aremoldable together, i.e. insert or over molding two pieces together orinjection molding one monolithic piece, the manufacturing steps of thebipolar plate 10 can be simplified, with less parts. Furthermore, thisprocess allows the ability to customize the size and shapes of thebipolar plate 10 and bipolar battery 100 according to the invention.

Now with reference back to FIGS. 1 and 2, the substrate 12 and thesubstrate 112 shown in FIGS. 4-8 includes perforations 13 along thesurface of the substrate 12, 112, and through the body extending throughan opposite surface. In the embodiment shown, the perforations 13 arecircular, but could otherwise be any shape. The perforations 13 arepositioned in a symmetrical grid pattern. The perforations 13 arepositioned in four quadrants of the shown substrate 12, 112. Having anumber of perforations 13 positioned in a symmetrical grid arrangementprovides even conductions through the substrate 12, 112 when lead foils14 are positioned on the opposite sides of the substrate 12, 112.

Additionally, the substrate 112 includes conductive particles, powders,and/or fibers 112 b along the surface and through the body of thesubstrate 112, as clearly shown in FIG. 5-9. In general, there aresurface areas of the substrate 112 are insulative, while other areas areconductive resulting from the conductive particles, powders, and/orfibers 112 b. As discussed above, the amount of conductive area can becontrolled through manufacturing of the substrate 112. For instance, thesurfaces of the substrate can be roughened to expose conductive areasthat may be custom in size and shape with respect to a whole exposedsurface side of the substrate 12, or the amount of conductive particles,powders, and/or fibers 112 b can be controlled with respect to theamount of insulative resin or thermoplastic 112 a. In the embodimentshown in FIGS. 5-9, the whole exterior surface of the substrate 112 hasbeen roughened to expose conductive particles, powders, and/or fibers 12b. Hence, the substrate is conductive on the exposed surface sides ofthe substrate and the lead foils 14 are positioned on the conductorparticles, powders, and/or fibers 112 b.

Now with reference to FIGS. 1, 2, 7, and 8, the lead foils 14 will bediscussed, which are positioned within the material receiving passageway11 b, on opposite sides of the substrate 12, 112. The lead foils 14 areconductive and connect with each other through the perforations 13. Morespecific, the lead foils 14 are mechanically and electrically connectedto each other in the embodiment shown. The substrate 12, 112 generallyis insulative, or only includes a limited area or conductivity based onconductor particles and/or fibers 112 b in the insulative resin orthermoplastic 112 a. As a result, perforations 13 are used to connectthe lead foils 14 with each other in the bipolar plate 10, notably for abipolar plate 10 having substrate 12 prepared exclusively frominsulative material. The lead foils 14 are welded together, as shown inFIG. 2, by resistance welding or other process known to the art. On theother hand, a bipolar plate 10 having a substrate 112, as shown in FIG.7, which includes the conductor particles or fibers 112 b homogenized inthe resin or thermoplastic 112 a, may also include perforations 113,which allow for further control and efficiency in conductivity betweenthe lead foils 14 and active materials 16, 18 in the bipolar plate 10according to the invention.

In either case, the perforations 13 can vary in size, shape, or gridpattern, but are large enough that the lead foil 14 can be positioned inand through the perforations 13 and connected to an adjacent lead foil14. The perforations 13 can be molded or milled into the substrate 12during manufacturing. With reference to FIGS. 1, 2, and 8, the leadfoils 14 are shown, being positioned on the both exposed surfaces of thesubstrate 12, 112 respectively, and dimensions to fit within thematerial receiving passageways 11 b of the frame 11. The lead foil 14 isdimensioned to securely fit in the material receiving passageway 11 b,such that the frame 11 encases each lead foil 14 positioned on bothsides of the substrate 12, 112. The leads foils 14 are mechanically andelectrically connected through the perforations 13, as shown in FIG. 7.

As shown in FIG. 9, the lead foils 14 may be inserted into the substratereceiving passageways 11, along with the substrate 12, 112 duringmanufacturing and assembly. The lead foils 14 may encased within theframe during insert molding, over molding, or similar manufacturingtechnique where the lead foils 14 and substrate 12, 112 are manufacturedwithin the substrate receiving passageways 11 a. The lead foils 14 arepositioned on opposite surfaces of the substrate 12, 112 and then eitherinserted or manufactured within the frame 11. It is possible to applythe lead foils 14 by known plating, vapor deposition, or cold flamespray methods.

It is also possible that the lead foil 14 is a paste having lead, whichis positioned along the front and rear surfaces of the substrate 12,112. The paste is spread across opposite surfaces (i.e. front and rearsurfaces) of the substrate 12, 112 and within the perforations 13. Thepaste connects both sides of the substrate 12, 112 through theperforations 13. The paste would be thick enough to provide connectivitybetween the pastes on each side, but should not be thicker than thematerial receiving passageway 11 b, considering an active material 16,18 is also positioned within the material receiving passageway 11 b.

With reference to FIGS. 2 and 5-9, the active materials 16, 18 are shownand positioned on exposed sides of the lead foils 14, facing away fromthe substrate 12, 112. The first layer of active material 16 is apositive active material paste (PAM) that is applied over one lead foil14, while a negative active material (NAM) is applied over the otherlead foil 14, which is the second active material 18. In the embodimentshown, the positive active material paste (PAM) and the negative activematerial (NAM) are paste of lead or lead oxide mixed with sulfuric acid,water, fiber, and carbon.

The thickness of the active materials 16, 18 (i.e. NAM and PAM) shouldnot extend outside the material receiving passageway 11 b of the frame11. Rather, the overall thickness T_(m) of the substrate 12, 112, leadfoils 14, and active materials 16, 18 is less than the thickness T_(f)of the frame 11.

The frame 11 encases the substrate 12, 112, lead foils 14, and activematerials 16, 18. As a result, when assembled the bipolar battery 100 isassembled in stacks of bipolar plates 10, the frame 11 acts as a supportand exterior surface for the bipolar battery 100. The number of assemblysteps and parts can be minimized. Furthermore, the bipolar battery 100and bipolar plate 10 can be easily customized for various applications,since the frame 11 and substrate 12 can be molded to various shapes andsizes.

Now with reference to FIGS. 3 and 4, spacers 22 are shown that stack andseal with the bipolar plates 10 according to the invention, and used tohold an electrolyte 20 for the bipolar battery 100.

The spacer 22 is shown between stacking adjacent bipolar plates 10. Thespacer 22 is essentially a casing having similar dimensions as the frame11 and includes an electrolyte receiving space 22 a, as shown in FIGS.3-6. The electrolyte receiving space 22 a is a hole through theelectrolyte receiving space 22 a, positioned substantially in the centerof the spacer 22 and holds an electrolyte 20. When sealed between twoadjacent bipolar plates 10, the spacer 22 prevents the electrolyte 20from leaking and allows the electrolyte 20 to provide conductivitybetween the bipolar plates 10.

As shown in FIGS. 5 and 6, at least one electrolyte receiving channel 22b is provided in the spacer 22, which is positioned on an outer surfaceof the spacer 22 and directed into the electrolyte receiving space 22 a.A user can provide electrolyte 20 through the electrolyte receivingchannel 22 b and into the electrolyte receiving space 22 a, after thespacer 22 is assembled and sealed with adjacent bipolar plates 10. Ingeneral, the electrolyte receiving channel 22 b is an opening in thespacer 22 that extends through the spacer 22 and into the electrolytereceiving space 22 a. However, other mechanisms or structures known tothe art could be used to allow ingress of electrolyte 20 into theelectrolyte receiving space 22 a. The receiving channel 22 b can beplugged or obstructed in some capacity when not utilized, or used tovent gases from the electrolyte receiving space 22 a.

The electrolyte 20 may be a variety of substances, including acid.However, the substance should be a substance that includes free ionsthat make that substance electrically conductive. The electrolyte 20 maybe a solution, a molten material, and/or a solid, which helps create abattery circuit through the electrolyte's ions. In the bipolar battery100 according to the invention, the active materials 16, 118 provide areaction that converts chemical energy to electrical energy, and theelectrolyte 20 allows the electrical energy to flow from the bipolarplate 10 to another bipolar plate 10, as well as to electrodes 36 of thebattery 100.

In the embodiment shown, the electrolyte 20 is an acid that is held inan absorbed glass mat (AGM) 21, as shown in FIGS. 4 and 5. Theelectrolyte 20 is held on the glass mat 21 by way of capillary action.Very thin glass fibers are woven into the glass mat 21 to increasesurface area enough to hold sufficient electrolyte 20 on the cells fortheir lifetime. The fibers that include the fine glass fibers glass mat21 do not absorb nor are affected by the acidic electrolyte 20 theyreside in. The dimension of the glass mat can be varied in size.However, in the embodiment shown, the glass mat 21 fits within theelectrolyte receiving space 22 a, but has a greater thickness than thatthe spacer 22. Additionally, the electrolyte receiving space 22 a, inthe embodiment shown, includes additionally space for a portion of theelectrolyte 20, and more specifically the glass mat 21. As a result, thedesign of the bipolar battery 100, according to the invention, allowsfor the spacer 22 holding the glass mat 21 to uniformly stack withadjacent bipolar plates 10, wherein the active materials 16, 18 sit onthe glass mat 21 containing the electrolyte 20.

It is also possible that the glass mat 21 is removed, and an electrolyte20, such as a gel electrolyte, is free to flow between adjacent activematerials 16, 18 between adjacent stacked bipolar plates 10 on eitherside of the spacer 22.

It is also possible, in other embodiments, that the spacer 22 is anextension of the frame 11. In general, the frame 11 includes a deepermaterial receiving passageway 11 b in order to encase the lead foils 14and active materials 16, 18, as well as electrolyte 20. Furthermore, ifthe frame 11 may be dimensioned such that the material receivingpassageways 11 b of stackable bipolar plates 10 can also hold an fiberglass mat 21 between each other, enclosing an encasing the lead foils14, active materials 16, 18, glass mat 21, and electrolyte 20 within thestacked and sealed bipolar plates 10. The frame 11 may include theelectrolyte receiving channel 22 b that extends through the frame andinto the material receiving passageway 11 b. In this embodiment, thebipolar plates 10 can be stacked onto each other and sealed.

Now with reference to FIGS. 4-6, the terminal sections 30 of the bipolarbattery 100 will be discussed, which cap the ends of the bipolar battery100. The terminal sections 30 stack on opposite sides of stacked bipolarplates 10, the number of bipolar plates 10 stacked next to each otherdepends on the electrical potential required of a specific batterydesign and shape.

Each terminal section 30 includes an additional layer of active material32, a terminal plate 34, an electrode 36, and an end plate 38. The endplates 38 are positioned on opposite ends of the stacked bipolar plates10, with the active material 32, the terminal plate 34 and electrode 36positioned within the end plate 38.

The active material 32 is provided to increase electrical flow throughthe bipolar battery 100, from one terminal section 30 to the otherterminal section 30. The active material 32 is made of material thatinteracts with an adjacent active material 16, 18 from an adjacentbipolar plate 10. Since a spacer 22 and electrolyte 20, as describedabove, is positioned on each stackable side of the bipolar plates 10, aspacer 22 is positioned between the terminal section 30 and an outsidebipolar plate 10. As a result, ions can freely flow through theelectrolyte 20 and onto the active material 32 of the terminal section30.

As shown in FIGS. 5-6, the terminal plate 34 is provided and encasedwithin the terminal section 30. The terminal plate 34 is conductive andgenerally a metal. The terminal plate 34 attaches to an electrode 36,which either an anode or a cathode of the bipolar battery 100. The anodeis defined as the electrode 36 at which electrons leave the cell andoxidation occurs, and the cathode as the electrode 36 at which electronsenter the cell and reduction occurs. Each electrode 36 may become eitherthe anode or the cathode depending on the direction of current throughthe cell. It is possible that both the terminal plate 34 and theelectrode 36 are formed as one piece.

As shown in FIGS. 4-6, the end plate 38 is non-conductive and providesstructural support to ends of the bipolar battery 100 according to theinvention. The end plate 38 includes a terminal receiving passageway 38a, which is a recess in which the terminal plate 34, electrode 36, andactive material 32 are positioned. Additionally, like the materialreceiving passageway 11 b, the terminal receiving passageway 38 aprovides enough clearance for an amount of electrolyte 20 to be encasedwith the terminal section 30, and specifically within the materialreceiving passageway 11 b along with the active material 32, terminalplate 34, and electrode 36. In the embodiment shown in FIGS. 5 and 6,the terminal receiving passageway 38 a provides enough space to receiveand enclose a portion of the glass mat 21, as well.

With reference to FIGS. 3 through 8, the assembly of the bipolar battery100 according to the invention will be further discussed.

The bipolar plate 10 is manufactured and assembled with the substrate12, 112 secured with the frame 11. The substrate 12, 112 includesperforations 13 and/or conductor particles or fibers 112 b, and isgenerally molded with the frame 11, either as a single or separatecomponent. Once the substrate 12, 112 is positioned within the frame 11,the lead foils 14 are positioned with the material receiving passageways11 b of the frame 11 on both exposed surfaces of the substrate 12, 112.The lead foils 14 are mechanically connected together through theperforations 13, and electrically connected through conductor particlesor fibers 112 b provided in the substrate 12, 112. A first activematerial 16 is then positioned in the material receiving passageways 11b on one side of the substrate 12, while the second active material 18is positioned on another side of the substrate within material receivingpassageways 11 b. As a result, the frame 11 encases the substrate 12,lead foils 14, and active materials 16, 18 within surface boundaries ofthe bipolar plate 10.

The bipolar plates 10 are stacked then next to each other with spacers22 provided between each stacked bipolar plate. Electrolyte 20 isprovided in the electrolyte receiving space 22 a, which is dimensionedsimilar to the material receiving passageway 11 b of the frame 11. Afiber glass matt 21 can be provided in the electrolyte receiving space22 a, as well, and an electrolyte 20 is provided into the fiber glassmatt 21 through the electrolyte receiving channel 22 b. The spacers 22and bipolar plates 10 evenly stack one next to the other, and aresubsequently sealed. Since the spacers 22 and stacked bipolar plates 10include non-conductive outer surfaces, the spacers 22 and frames 11 ofthe bipolar plates 10 create an outer shell for the bipolar battery 100.The frames 11 of the bipolar plates 10 and spacers 22 can be secured toeach other by any method known to the art such that the touchingsurfaces of the spacers 22 and the frame 11 are secured to each otherand sealed. For instance, an adhesive can be used to connect and sealthe surfaces together. Additionally, once the terminal sections 30 areassembled, they may be positioned on the stacked bipolar plates 10 andspacers 22, and then sealed in the same manner.

It is also possible, that the end plates 38, the spacer 22, and theframe 11 include securing mechanisms (not shown), such as jointtechnique or fastener, to connect the pieces of the bipolar battery 100together. Then a sealant may be applied to provide a seal around thebipolar battery 100, and more specifically, a seal around the connectingend plates 38, spacers 22, and frame 11.

It is also possible, that the bipolar plates 10 are stacked and securednext to each other without a spacer 22. However, the material receivingpassageway 11 b should be large enough to hold and encase the lead foils14, active materials 16, 18 and an electrolyte 20, including a fiberglass mat 21, when the stacked bipolar plates 10 are sealed together.Furthermore, the frame 11 should include at least one electrolytereceiving channel 22 b positioned in an extension of the frame 11, sothat electrolyte 20 can be provided into the material receivingpassageway 11 b of the frame 11, or allow venting of the electrolyte 20.

The number of bipolar plates 10 used in the bipolar battery 100 is amatter of design choice, dependent upon the size of battery 100 and theelectrical potential required. In the embodiment shown, there are atleast three bipolar plates 10 stacked next to each other. On oppositesends of the stacked bipolar plates 10 and electrolyte 20 are terminalsections 30, which include a layer of active material 32, a terminalplate 34 and electrode 36, as well as an end plate 38. In the embodimentshown, the outer surfaces of the spacer 22 and the frame 11 aresubstantially flush with each other when stacked and sealed. This designprovides a smooth outer support surface. However, it is possible thatirregularities in the surface may exist. For instance, the spacer 22 maybe larger than the frame 11; however, the electrolyte receiving space 22a cannot be larger than the frame 11. Additionally, the materialreceiving passageway 11 b cannot be larger than the spacer 22. In eithercase, it may be difficult to seal the spacer 22 and bipolar plates 10,and the electrolyte 20 could leak from the bipolar battery 100 afterassembly and the electrolyte 20 is positioned between adjacent bipolarplates 10.

Furthermore, when the end plate 38 is stacked next to an adjacent spacer22 and/or frame 11 of an adjacent bipolar plate 10, the outer surfacesof end plate 38, the spacer 22 and the frame 11 should be substantiallyflush. However, it is possible that irregularities in the surface mayexist. For instance, the end plate 38 may be a bit larger than thespacer 22, which may be larger than the frame 11. Nonetheless, terminalreceiving passageway 38 a should not be larger than the receivingchannel 22 b or the frame 11. Additionally, the terminal receivingpassageway 38 a should not be larger than the material receivingpassageway 11 b or the frame, or the end plate 38 should not be smallerthan then the spacer 22. In either case, the electrolyte 20 may leakfrom the bipolar battery 100 after assembly and the electrolyte 20 isprovided between stacked bipolar plates 10. In general, the frame 11supports the bipolar plate 10, encasing the substrate 12, lead foils 14,and active materials 16, 18, as well as electrolyte. When stacked, thebipolar plates 10, with adjacent spacers 20 and stacked terminalsections 30 provide an outer support surface for the bipolar battery100. This construction provides a bipolar battery 100 having asimplified designed, having fewer manufacturing steps and fewer partsthan required in the prior art. Since the frame 10, spacer 22, and endplate 38 are insulative plastic and moldable, the bipolar battery 100can be customized to accommodate shape and size requirements dependenton electrical potential and use.

In another embodiment, as shown in FIG. 5, a protective casing 200 isfurther provided, that encloses the bipolar battery 100 according to theinvention. The casing 200 would include body 202, a cover 204, and anelectrode receiving space 206, in order for the electrode 36 to extendout of the casing 200. Unlike an external structure of the bipolarbattery 100, the casing 20 can be used to house the bipolar battery 100and provide greater protection.

In another embodiment, as shown in FIG. 10, the bipolar plate 10 of theabove embodiments may further include a plurality of standoffs 40positioned on each side of the substrate 12, 112. The standoffs 40 areintegrally formed on each side of the substrate 12, 112, and are spacedapart from the perforations 13. In the embodiment shown in FIG. 10, thelead foils 14 positioned on the substrate 12, 112, have holes 41corresponding to the standoffs 40, such that the lead foils 14accommodate the standoffs 40 and are positioned on the surfaces of thesubstrate 12, 112.

When the bipolar plates 10 with standoffs 40 are assembled into abipolar battery, the frames 11 and standoffs 40 of one bipolar plate 10are respectively attached to the frames 11 and standoffs 40 of anotherbipolar plate 10, providing uniform spacing and structural integritybetween the plates 10 of the bipolar battery assembly. The frame 11 ofone bipolar plate 10 may be attached to the frame 11 of another bipolarplate 10 by any type of welding known to those with ordinary skill inthe art including ultrasonic welding, chemical welding, solvent welding,spin welding, or hot-plate welding. The frame 11 may alternatively beattached to another frame 11 by any mechanical connection known to thosewith ordinary skill in the art including a hook and latch or a ball andsocket connection. The standoffs 40 of one bipolar plate 10 may beattached to the standoffs 40 of another bipolar plate 10 by any type ofplastic welding known to those with ordinary skill in the art includingultrasonic welding, chemical welding, solvent welding, spin welding, orhot-plate welding. The standoffs 40 may alternatively be attached toother standoffs 40 by any type of mechanical connection known to thosewith ordinary skill in the art including a hook and latch or a ball andsocket connection.

The foregoing illustrates some of the possibilities for practicing theinvention. Many other embodiments are possible within the scope andspirit of the invention. It is, therefore, intended that the foregoingdescription be regarded as illustrative rather than limiting, and thatthe scope of the invention is given by the appended claims together withtheir full range of equivalents.

What is claimed is:
 1. A bipolar battery plate for a bipolar battery,comprising: a frame; a substrate positioned within the frame and havinga plurality of perforations, and a plurality of standoffs integrallyformed on opposing side surfaces thereof; a first lead layer positionedon one side of the substrate; a second lead layer positioned on anotherside of the substrate, the first and second lead layers electricallyconnected to each other through the plurality of perforations; apositive active material (PAM) positioned on a surface of the first leadlayer; and a negative active material (NAM) positioned on a surface ofthe second lead layer.
 2. The bipolar battery plate according to claim1, wherein the first lead layer and the second lead layer have holescorresponding to the plurality of standoffs that align with thestandoffs when the first and second lead layers are positioned on eachside of the substrate.
 3. The bipolar battery plate according to claim1, wherein the frame is a moldable insulative polymer.
 4. The bipolarbattery plate according to claim 1, wherein the frame is an outer wallof the bipolar battery that provides structural support for the bipolarbattery.
 5. The bipolar battery plate according to claim 1, wherein thesubstrate is prepared from the same material as the frame in a one piececonstruction.
 6. The bipolar battery plate according to claim 1, whereinthe substrate is a non-conductive insulative plastic having conductiveparticles that are homogeneously dispersed throughout the insulativeplastic.
 7. The bipolar battery plate according to claim 6, wherein thesubstrate includes conductive surfaces where the surfaces of thesubstrate are roughened by a chemical or abrasion and the conductorparticles are exposed outside the insulative plastic.
 8. The bipolarbattery plate according to claim 1, wherein the perforations arepositioned along and extending through the substrate.
 9. The bipolarbattery plate according to claim 8, wherein the lead layers are leadfoils that are conductive through the perforations.
 10. The bipolarbattery plate according to claim 9, wherein the lead foils aremechanically and electrically connected to each other through theperforations.
 11. The bipolar battery plate according to claim 10,wherein the lead foils are welded together by resistance welding. 12.The bipolar battery plate according to claim 1, wherein first and secondlead layers are a lead paste that is positioned along front and rearsurfaces of the substrate.
 13. The bipolar battery plate according toclaim 12, wherein first lead layer is spread across the front surface ofthe substrate and within at least one of the perforations so that thatfirst lead layer connects to the second lead layer on an opposite side.14. The bipolar battery plate according to claim 1, wherein the positiveactive material is a paste applied over the first lead layer and thenegative active material is a paste spread over the second lead layer.15. A bipolar battery, comprising a plurality of plates positioned nextto each other, each plate having, a frame; a substrate positioned withinthe frame having a plurality of perforations, and a plurality ofstandoffs integrally formed on opposing side surfaces thereof; a firstlead layer positioned on one side of the substrate; a second lead layerpositioned on another side of the substrate, the first and second leadlayer electrically connected to each through the plurality ofperforations; a positive active material (PAM) positioned on a surfaceof the first lead layer; a negative active material (NAM) positioned ona surface of the second lead layer; a pair of terminal sectionspositioned on opposite ends of the stacked plurality of bipolar plates;and an electrolyte positioned between each of the plurality of bipolarplates and the pair of terminal sections.
 16. The bipolar battery plateaccording to claim 15, wherein the first lead layer and the second leadlayer have holes corresponding to the plurality of standoffs that alignwith the standoffs when the first and second lead layers are positionedon each side of the substrate.
 17. The bipolar battery plate accordingto claim 15, wherein the frames on the plurality of plates are attachedtogether.
 18. The bipolar battery plate according to claim 15, whereinthe plurality of standoffs of one plate are attached to the plurality ofstandoffs of another plate.
 19. The bipolar battery plate according toclaim 18, wherein the standoffs of one plate are attached to thestandoffs of another plate by ultrasonic welding, chemical welding,solvent welding, spin welding, or hot-plate welding.
 20. The bipolarbattery plate according to claim 18, wherein the standoffs of one plateare attached to the standoffs of another plate by a hook and latch orball and socket connection.